The invention relates to anti-theft devices for automobiles. It relates, more particularly, to such devices which inhibit the opening of locked vehicle doors by manipulation of the internal latch button by means of a bent wire or other artifact from the outside.
Theft of automobiles is one of the most common criminal acts in this country and one of the most difficult to prevent. Moreover, stolen cars are relatively rarely recovered, and in many instances the recovered vehicle is found in a condition which prevents the full use and enjoyment by the owner thereafter.
The reason for the widespread car thievery, ranging from temporary `borrowing` for joyrides to organized rings which `steal to order,` is the ease with which the conventional locks of a vehicle door can be circumvented, and the equal ease with which a thief, once inside the car, can short-circuit the ignition and drive off with his `loot.` By far the most common method for gaining entry into an automobile is the use of a bent coathanger, or a more purposebuilt artifact of similar form, to lift up the locking button of a door lock. These locking, or latch, buttons have a mushroom head, for ease of operation by the owner of the car, and access to them can readily be gained by passing the thin wire through the weatherstrip around a window, or by forcing the `no-draft` window slightly ajar.
The prior art has addressed the problem of making latch buttons -- and other door lock operators on the inside -- safe from such simple techniques, without success. U.S. Pat. No. 3,416,827 to COLE describes a portable lock of considerable complexity which may be attached to door hardware projecting from the inner face of a car door. The COLE device does not, however, encompass a secure means for preventing the manipulation of latching buttons and is only applicable to the small minority of vehicles in service which do not have such buttons in their door lock systems.
U.S. Pat. No. 2,793,064 to BUDOFF does address itself to the problem of securing the latching button, by providing a cap member with a locking tongue, to be slipped over on top of the button and, subsequently, secured to a lock on the door. The approach of BUDOFF is not, however, applicable to the vast majority of vehicles in which the latch button is mechanically linked to the door lock proper in both directions of operation. In such doors the latch button must be free to move upward when the door is opened from the outside by a key properly inserted into the lock. Since the device of BUDOFF does not permit such movement, or if it does is useless for securing the latch button in the first place, it secures the door not only against a would-be thief but also against the rightful owner of the vehicle; except in the few cases where the door lock can be unlocked without requiring the lifting of the latch button.
It is, therefore, a prime object of the invention to provide a device by means of which a latch button forming part of an automobile door lock system may be secured against engagement by a bent wire artifact, without affecting the normal operation of the button by hand or via the door key.
It is a further object of the invention to teach the construction of a simple anti-theft device readily incorporated in the design of automobile door lock hardware, or retrofitted thereto, which would attain the prime object defined above.
It is yet another object of the invention to provide such an anti-theft device in a form which is economical to produce and simple to install.
It is also an object of the invention to teach the use and application of secondary locking mechanisms, in anti-theft devices of such nature, further ensuring that no portion of the combined latch button and anti-theft device system is accessible to engagement by an externally manipulated wire antifact or the like.